Index: wp-includes/post-template.php
===================================================================
--- wp-includes/post-template.php	(revision 11141)
+++ wp-includes/post-template.php	(working copy)
@@ -224,7 +224,7 @@
 		} else {
 			$output = balanceTags($output);
 			if ( ! empty($more_link_text) )
-				$output .= ' <a href="'. get_permalink() . "#more-$id\" class=\"more-link\">$more_link_text</a>";
+				$output .= apply_filters( 'the_content_more_link', ' <a href="'. get_permalink() . "#more-$id\" class=\"more-link\">$more_link_text</a>", $more_link_text );
 		}
 
 	}